Bypassing certificate pinning

ABSTRACT

A client application performs certificate pinning as a means of authenticating the identity of a server. A proxy is interposed in the communications path of the client and the hosting server and provides a proxy security certificate to the client. In response to the client extracting a proxy authentication component from the proxy security certificate, operation of the client is paused and a hosting server authentication component is extracted from a hosting server security certificate. The client operation is resumed, providing the extracted hosting server authentication component to the client, in substitution for the proxy authentication component. Based on receiving the extracted hosting server authentication component, the client authenticates the proxy to receive communications directed to the hosting server.

BACKGROUND

The present disclosure relates to methods for authenticating a computerserver. More specifically, the present disclosure relates to a method tobypass certificate pinning in systems that perform certificate pinningto authenticate a server.

SUMMARY

In an embodiment of the present disclosure, a method for authenticatinga hosting server features a proxy interposed in the communication pathbetween a client and the hosting server. The client and the proxy eachoperate in a computing device. The method includes receiving a requestfor a security certificate from the client and, in response,communicating a security certificate associated with the proxy to theclient. A feature of the method detects the client extracting a proxyserver authentication component from the proxy server securitycertificate. Detecting the client extracting the proxy serverauthentication component pauses operation of the client.

The method further features extracting a hosting server authenticationcomponent from a server security certificate associated with the hostingserver. The client operation is resumed, and resuming the clientoperation includes providing to the client the extracted hosting serverauthentication component in substitution for the proxy serverauthentication component. Based on receiving the extracted hostingserver authentication certificate, the client authenticates the proxy toreceive client communications directed to the hosting server.

In another feature of the method, an extraction function operates toextract the proxy server authentication component from the proxy serversecurity certificate. Instrumenting the extraction function operates todetect the client extracting the proxy server authentication componentfrom the proxy server security certificate.

An aspect of the disclosure includes the proxy receiving a clientcommunication directed to the hosting server. The proxy receiving theclient communication is based at least in part on the clientauthenticating the proxy to receive client communications directed tothe hosting server using the extracted hosting authentication component.In another aspect of the disclosure, the client performs certificatepinning authentication of the hosting server. Providing the hostingserver authentication component to the client, in substitution for theproxy server authentication component, satisfies the certificate pinningauthentication.

It is another feature of the disclosure that a computer program productincludes instructions executable by a computing device to perform themethod. It is yet another feature of the disclosure that a computingsystem can embody structures configured to perform aspects of themethod.

The above summary is not intended to describe each illustratedembodiment or every implementation of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings included in the present application are incorporated into,and form part of, the specification. They illustrate embodiments of thepresent disclosure and, along with the description, serve to explain theprinciples of the disclosure. The drawings are only illustrative ofcertain embodiments and do not limit the disclosure.

FIG. 1 is a flow diagram illustrating an example of a client and serverestablishing secure communications, according to aspects of thedisclosure

FIG. 2 is a block diagram illustrating an example computing system forauthenticating a server, according to aspects of the disclosure.

FIG. 3 is a flow diagram illustrating an example flow to establishsecure communications including an analyzer and a scanner, according toaspects of the disclosure.

FIG. 4 is a flow diagram that illustrates an example flow toauthenticate a server, according to aspects of the disclosure.

FIG. 5 is a flowchart that illustrates an example method to authenticatea server, according to aspects of the disclosure.

FIG. 6 is a block diagram illustrating a computer program product thatmay embody methods and structures of the disclosure.

While the invention is amenable to various modifications and alternativeforms, specifics thereof are shown by way of example in the drawings andare described, herein, in detail. It should be understood, however, thatthe intention is not to limit the invention to the particularembodiments described. On the contrary, the intention is to cover allmodifications, equivalents, and alternatives falling within the spiritand scope of the invention.

DETAILED DESCRIPTION

Aspects of the present disclosure relate to computing applications thatauthenticate the identity of a server hosting resources or servicesaccessed by the client. More particular aspects of the disclosure relateto bypassing certificate pinning verification of security certificates.While the present disclosure is not necessarily limited to suchapplications, various aspects of the disclosure may be appreciatedthrough a discussion of various examples using this context.

Applications (hereinafter, “clients”) executing on, or within, acomputer or computing device may access resources or services in othercomputers or computer systems (hereinafter, “server”). “Computer”, and“client computer”, as used in the disclosure in the context of anembodiment of a client application, refer to any of a variety ofcomputing or electronic devices, including a virtual machine (VM) of acomputer or computing device, of which a client application may be acomponent, or on/in which a client application may execute, and as areparticularly disclosed in the present specification. “Server”, as usedin the disclosure in the context of a client application accessing aresource or service, refers to a computer or computing system that hostsresources or services accessed by the client application. In othercontexts, “computer” and “server” are understood to have their commonmeaning with regard to general purpose computing devices in variousother computing system roles.

Clients may be, or include, programs operating on a computer, or withina virtual machine of a computer. Clients may be, or include, “apps”,such as those used on a mobile device (e.g., a cell phone or tabletcomputer). Clients may be, or include, programs and/or hardwarecomponents, for example, of a device included in a household appliance,such as a network-connected monitoring or control device of arefrigerator, or personal device (e.g., a fitness monitor). A client mayinclude, or may be embodied, in whole or in part, in a hardwarecomponent of a computer or computing device.

Clients may access resources or services by means of a communicationsnetwork that connects a client to a server. A communications network maybe, or include, for example, a corporate (or home) intranet (e.g., a LANor WAN), the Internet, or a cellular communications network (e.g.,mobile phone networks). Alternatively, a client may have some form ofdirect connection to a server, such as an I/O interface cable. Clientsmay access a server, for example, to request data, such as a web page; aservice, such as a banking transaction; or a resource, such as storageor a virtual machine in a computer server or a computing cloud.

In some cases, a client may communicate information to a server in whichsome, or all, of the client information may be confidential orsensitive. A client may need, therefore, to assure that the server is“trusted”. A server may be trusted in the sense that the server isauthorized to receive or utilize client information. For example, aclient may trust a server not to expose client information to otherapplications or computers. A server may be trusted in the sense that theclient may be confident that the server will not return information (or,data) to the client that might compromise the operations of the client,the client computer, or a computer or server that the client, or theclient computer, may communicate with. For example, a client may trust aserver not to inadvertently, or maliciously, transmit or install malwarein the client or the computing environment (e.g., the client computer,or VM of a client computer) in which the client operates.

As part of accessing resources or services of a trusted server, aclient, or a client computer, may authenticate the identity of a servercommunicating with the client to assure the server is actually theintended server. A particular type of security threat is a “Man in theMiddle (MiTM)” attack. To effect a MiTM attack, an attacker is insertedin the communications path (or, “communications channel”) between aclient and a server. An attacker may perform any of a variety of methodsto accomplish such insertion. The result of such insertion is that theattacker may then intercept communications between the client and anintended server. The attacker may simply monitor the communications, forexample to “snoop” the client information, or may communicate theinformation to an unauthorized user (e.g., to extract a credit cardnumber for unauthorized use by another). An attacker may modifyinformation in the communications, for example, to expose the client tomalware that then may be installed on the client computer.

Prior to exchanging confidential or sensitive information with a server,a client may authenticate the identity of a server as a trusted server.Having authenticated a server as trusted, a client may establish asecure communications “session” with the server, such that an attackercannot monitor communications between the client and the server. Forexample, a client and server may establish a secure session to encrypttheir communications, such that an attacker cannot monitor or modifytheir communications. A client and server may use, for example,Transport Layer Security (TLS) to mutually select a particular method ofencrypting client-server communications. To establish a secure sessionusing TLS, for example, a client may communicate a set of cryptographicinformation (e.g., a random number and a suite of ciphers) to use forencrypting client-server communications. Correspondingly, the server mayreturn a set of cryptographic information (e.g., a random number and aparticular cipher of those the client sent) to use for encryptingclient-server communications.

Prior to, or as part of, establishing a secure session, a client mayauthenticate the server as the actual, trusted server. A client may usea securely signed digital identity (or, “security”) certificate,associated with the server, to verify the authenticity of the serverproviding that certificate. As part of establishing a secure session(e.g., using TLS) with a server, a client may request that the serverprovide the security certificate to the client. The client may use thesecurity certificate received from the server to verify the authenticityof the server. The certificate may include authentication componentinformation about the server, such as a public encryption key used bythe Certificate Authority (CA).

If the certificate is valid, the client may then complete establishingthe secure session (e.g., begin to exchange encrypted client informationwith the server). If the certificate is not valid (e.g., the CertificateAuthority that signed the certificate is not a trusted CA, the digitalsignature of the CA is not valid, or the public key of the server,included in the certificate, does not match a value the client expects),the client may terminate communications with the server.

FIG. 1 illustrates an example client and server flow 100 to establish asecure (e.g., TLS) session to communicate with a server using, forexample, a common Internet protocol such as Transmission ControlProtocol (TCP). TCP setup 130 establishes the TCP session. As part ofTCP setup 130 client 102 sends a client open request (110) to server104. Server 104 responds with a server acknowledgement (112), and theclient completes TCP setup 130 by sending the server a clientacknowledgement (114).

The TCP session itself may simply open a communications channel fortransmitting messages between the client and the server. The TCP sessionmay not otherwise be secure against a third party device or programeavesdropping upon, or intercepting and modifying, client and servermessages. Accordingly, the client and server may perform TLS setup 140to establish a secure communications session. Client 102 may send a“client hello” message (116) to initiate TLS setup 140. The client hellomessage may include cryptographic information to negotiate with theserver, for example, a secure cipher for encrypting subsequentcommunications with the server. Server 104 may then respond by sending a“server hello” message (118), and the server hello message may includecryptographic information to complete negotiating the cipher.

A client may incorporate authentication of the server identity in theprocess to establish a secure session, such as in establishing TLS setup140. To authenticate the server as a trusted server, a client mayrequest that the server return a security certificate. For example, aclient may include a request for a security certificate in a clienthello. The server may return the security certificate, for example in aserver hello. For example, the client hello sent as part of TLS setup140 may include a request for server 104 to provide a securitycertificate associated with the server. Server 104 may return thecertificate in the server hello sent to the client.

The information in the security certificate may include one or moreauthentication components that client 102 may use to verify theauthenticity of server 104. For example, a certificate may include thepublic encryption key of the server. The client may utilize anextraction function to extract particular authentication componentinformation, such as a public key, from a server certificate. Anextraction function may be a function of a component (e.g., a utility ofan operating system or other program) on, or in communication with, theclient computer. The client may access the extraction function by aninterface, such as an API or a hardware interface.

To authenticate a server security certificate, a client may perform“certificate pinning”. In performing certificate pinning, a client mayextract particular information from a security certificate. The clientmay compare the information from the security certificate, or aderivative of the information, to information, or an equivalentderivative thereof, stored securely within or by the client. Forexample, a client may have (or “know”) a trusted “pin” associated with atrusted security certificate, or derived from information included in atrusted security certificate. A client may derive a trusted pin for apreviously trusted server certificate, for example, as a hash of thepublic key of the server. A client may store the pin in a securelocation; for example, a client may embed the pin within a client codemodule (e.g., a binary executable or data module). Upon receiving asecurity certificate, a client may form a pin from an authenticationcomponent included in a security certificate and compare that pin to thetrusted pin the client has stored (or knows).

For example, FIG. 1 illustrates client 102 performing certificatepinning 150. In performing the certificate pinning, client 102 mayextract the public key of server 104 from a security certificatereceived from server 104 (e.g., in the server hello). Client 102 mayhave formed a pin by means of a hash of the public key of server 104 andmay have embedded the pin in a binary executable or date file of client102. Client 102 may then form a hash (using, for example, the hashingfunction used to form the pin) of the public key of the server includedin the security certificate received from server 104. Client 102 maycompare the hash formed from the public key in the security certificateto the pin, to check the authenticity of the security certificate (120),and thereby authenticate server 104 as trusted to communicate withclient 102.

Clients that use resources or services over a network can expose acomputer to a security threat (e.g., a MiTM attack to interceptinformation or compromise the security of the computer executing theclient). Correspondingly, client application developers or computersystem administrators, for example, may test the client to verify thatthe client accesses only trusted servers or trusted resources of trustedservers.

A system for testing a client application may include an analyzer and ascanner. An analyzer may cause the client to access network servers orresources of particular network servers (e.g., particular World-WideWeb, “WWW”, pages). For example, an analyzer may simulate a human userof a mobile device app, or may access a human graphical user interface(GUI), a command line (CLI) interface, or an application-programminginterface (API). The client may be embodied, in whole or in part, in aprogram and the program may include one or more of a GUI, a CLI, or anAPI. The GUI, CLI, or API may activate the client to perform a function.The client may be embodied, in whole or in part, in a hardwarecomponent, and the hardware component may provide interfaces to activatethe client to perform a function. The analyzer may provide varyinginputs to the client to cause the client to access variousnetwork-connected servers or resources of the servers.

In response to analyzer stimuli, the client may access a server using anetwork identifier for the server, such as a WWW Universal ResourceLocator (URL) for a web page or service hosted on a server, or theInternet IP address of a server or resource of a server. A scanner maybe inserted in the communications channel between the client and thenetwork, or between the client and particular servers. A scanner may beinserted in the communications channel as a network “proxy” between theclient and the network or servers.

A scanner may inspect, record, or access the server, and/or resource orservices the client accesses, which may be referred to as “crawling” theclient application “backend” (hereinafter, “crawling” refers to anyoperation of a scanner to inspect, record, or access servers, orresources or services of a server). Crawling the backend may determinethe addresses or identities of servers, resources, or services to whicha client directs a request. Crawling the backend may determine thecontent of information returned from a server, or the type or results ofservices performed or hosted on, or by, a server. A scanner may crawlthe backend of a client application to detect security exposures orthreats to, for example, the client, the client computer, or to acomputing system, or components thereof, in communication with theclient or the client computer. A scanner may simulate responses from theservers, and may forward actual or simulated responses to a client.

FIG. 2 illustrates a computing system 200 in which a client applicationmay access resources on network-connected servers, and an analyzer andscanner may operate to test the client for access to un-trusted orinsecure (e.g., those that have security vulnerabilities or pose asecurity threat) servers or resources. FIG. 2 depicts computer 202 asconnected 262 via a network 260 (e.g., the Internet or an intranet) toservers 230, 240, and 250. In some embodiments, computer 202 may bedirectly connected (not shown) to, or in communication with, one or moreservers.

Computer 202 includes a processor 204 and a memory 206. A processor maybe a single processor, a processor chip, a multi-core processor, amulti-threaded (e.g., SMT) processor, or any device capable of executingcomputing instructions. A computer may include a plurality of one or avariety of these types of processors. A memory may be a main memory, acache memory, or a flash memory, for example. A computer may include aplurality of one or a variety of these types of memories.

In some embodiments, computer 202 may be a general or special purposecomputer, a mobile device (e.g., a tablet computer or cell-phone), awearable device (e.g., a fitness monitor), an internet-connected device(e.g., a device in the “Internet of Things”), a server computer, or anycomponent of a computer, or computing system, capable of connecting to anetwork, such as the internet, and capable of hosting, or executing, aclient application. In embodiments, a client application may use aprocessor, such as processor 204, and memory, such as memory 206, toexecute programming instructions. In other embodiments a clientapplication may be, or may include, a hardware component, and thehardware component may be included in a computing device in which theclient application executes or operates within.

An operating system may host, or provide the environment for a client(e.g., an application program) to execute. An operating system mayexecute using hardware within a computer (e.g., processor 204 and memory206 of computer 202) and a client may use the hardware within thecomputer under the control of the operating system. A computer mayprovide virtual machines, and the computer may include a hypervisor tofacilitate providing virtual machines. A hypervisor may allocate to,and/or may control the use of, hardware and other resources (e.g.,interrupt numbers) of the computer to an operating system.

For example, computer 202 includes a hypervisor 208, an operating system210, and a virtual machine, VM 218. The hypervisor may allocate aprocessor, such as processor 204, and portions of memory 206 tooperating system 210, which in turn may be used by a client application,such as client application 214, executing on, or operating within,computer 202. An operating system may execute within a VM. For example,an operating system (not shown) may execute within the environment of VM218. Client 214 executes on, or operates within, computer 202 and maydirectly use the hardware or resources of the computer, or may use thehardware or resources under the control of operating system 210 (or, anoperating system executing within VM 218).

Client 214 may use resources in servers—such as servers 230, 240, and250—connected to network 260. For example, server 230 hosts web page232; server 240 hosts a service 242 (e.g., financial transactionprocessing); and server 250 hosts cloud resource 252 (e.g., cloudstorage or a VM). To access the resources or services, a clientapplication may use a network address or identifier. For example, client214 may know web page 232 or service 242 as a WWW URL (e.g.,“www.service.com”—not intended herein to be any particular or actual WWWURL). Client 214 may know cloud resource by an IP address (e.g.,192.100.101.101—not intended herein to be the IP address of anyparticular or actual network entity).

A client application testing system may include analyzer 212, executingon or within computer 202, and a scanner 222. In an embodiment, ananalyzer may execute on or within a computer in which a client executes,as illustrated by analyzer 212 within computer 202 in FIG. 3.Alternatively, (not shown) an analyzer may execute in a differentcomputer in communication with a client (e.g., in a computer, such as aworkstation or laptop, connected in some manner to the computer in whichthe client executes or operates).

In an embodiment, a scanner may be a component of a computer on, orwithin, which an analyzer executes, or may be a component of a computeron, or within, which a client executes. For example, scanner 222 may bea component of computer 202. In other embodiments, a scanner may be acomponent of a computer, or computing system, in communication with aclient, or a computer in which a client executes or operates. Forexample, scanner 222 may be a component of a computer, or computingsystem, connected to computer 202, or in communication with client 214,by means of network 260. In embodiments, a scanner may be a program, maybe a hardware component, or may be combination of these. In someembodiments, an analyzer can be a function of, or included in, ascanner.

Analyzer 212 may access interfaces 216 (e.g., GUIs, CLIs, or APIs) ofclient 214 to activate a function of client 214. Activating the functionmay cause client 214 to access servers on network 260 (or, anothernetwork, not shown). For example, analyzer 212 may activate a functionof client 214 that requests (231) web page 232 from server 230. Client214 may identify web page 232 by a WWW URL, an IP address, or some othername or identity, and may identify server 230, for example, by an IPaddress. Analyzer 212 may activate a function of client 214 thatrequests (241) access to, or performance of, service 242. Client 214 mayidentify the service by a URL, an IP address, or some other name oridentity, and may identify server 240, for example, by an IP address.Analyzer 212 may activate a function of client 214 that requests (251)access to cloud resource 252 in server 250. Client 214 may identify thecloud resource by a URL, an IP address, or some other name or identity,and may identify server 250, for example, by an IP address.

In embodiments, scanner 222 may operate as a proxy. Client 214 may knowthe IP address of scanner 222, and may communicate (220) with thescanner, acting as a proxy. Client 214 may receive communications fromservers via scanner 222 acting as a proxy. Accordingly, scanner 222 mayreceive (220) communications from client 214 targeting servers, orserver resources, on (e.g., servers 230, 240, or 250) or, incommunication with (not shown), network 260, and may forward (224) thesecommunications to the intended servers. The scanner may receive (e.g.,231, 241, or 251) responses, or other communications, from the serversand may forward these (220) to client 214. Scanner 222, acting as aproxy, may monitor the particular network addresses (e.g., URLs or IPaddresses) the client targets.

An embodiment may employ secure communications for a client applicationto communicate with a server. For example, client 214 may communicatewith servers 230, 240, or 250 using a TLS session. In operating as aproxy, a scanner then may be required to participate in the clientestablishing a TLS session with a server.

FIG. 3 illustrates an example flow 300 of a client applicationestablishing a secure session (e.g., a TLS session) with a server in asystem, such as system 200, that includes a scanner operating as a proxybetween the client and the server. Client application 308 executes onclient device 304. Client device 304 may be any of a variety ofcomputers, or computing devices, such as previously disclosed; forexample, client device 304 may be a mobile device, a tablet computer, alaptop, a server, or a VM operating within a computing device. Client308 may access servers, such as server 306, directly or over a network,for example. Analyzer 302 may interact with client 308 to cause it toaccess the servers, or resources on the servers.

To access resources or servers, client 308 may use a securecommunication session, such as a TLS session. Scanner 310 operates as aproxy between client 308 and a server, such as server 306. Accordingly,client 308 establishes TLS session TLS-1 (320) with the scanner 310. Thescanner establishes TLS session TLS-2 (330) with server 306, which maybe a target of client 308 communications to access server 306, or aresource hosted on server 306. Client 308 initiates (322) establishingthe TLS-1 session and the scanner responds (324) to enable TLS-1 to beestablished. Client 308 may send a client hello and scanner 310 may senda server hello (both not shown) to establish TLS-1. Client 308 mayrequest scanner 310 to provide a security certificate to establish thescanner as a trusted (proxy) server and to complete TLS-1 setup 320.

In establishing TLS-2 (330) with server 306, scanner 310 initiates (334)the session. Server 306 responds (332) to complete establishing TLS-2.Scanner 310 may send a client hello and server 306 may send a serverhello (both not shown) to establish TLS-2. Scanner 310 may requestserver 306 to provide a security certificate. Scanner 310 and server306, in establishing TLS-2, may determine a cipher, known privatelybetween the scanner and server, for encrypting communications betweenthem.

Analyzer 302 may interact (312) with client 308, and, in response,client 308 may send communications to access server 306, or resources orservices hosted on server 306. For purposes of illustrating thedisclosure, but not limiting the embodiments, the communications may bein the form of messages sent from client 308 to server 306, andvice-versa. The messages may be associated with accesses to resources orservice hosted on server 306, and client 308 may encrypt messagestargeting server 306 using the TLS-1 cipher. Client 308 may communicatethe messages using the TLS-1 session and scanner 310 may receive theclient 308 messages directed to server 306. Scanner 310 may decrypt themessages using the TLS-1 cipher and may record the resources or servicestargeted (e.g., an IP address or WWW URL) at server 306. Scanner 310 maycommunicate the messages from client 308 to server 306 using the TLS-2session, and may use the TLS-2 cipher to encrypt the messages.

Server 306 may respond to the client 308 messages and send messagesdirected to client 308. The messages may return information from server306 (e.g., the contents of a web page, or results of a transactionservice) in response to the messages from client 308. Server 306 maycommunicate the messages to client 308 using the TLS-2 session, and mayencrypt the messages using the TLS-2 cipher. Scanner 310 may receive themessages from server 306 and may decrypt the messages using the TLS-2cipher. Scanner 310 may record information form server 306 regarding theresources in the client 308 messages. Scanner 310 may communicate themessages to client 308 using the TLS-1 session, and may use the TLS-1cipher to encrypt the messages.

A client application may use certificate pinning, and the flow asillustrated in the example of FIG. 3, may not succeed in establishing asecure session between the client and a proxy (e.g., TLS-1 betweenclient 308 and scanner 310). For example, client 308 may have a hashcode (as an example of a pin) for the public key associated with server306 and may embed that hash code in a module (or hardware component)included in or with client 308. Client 308, at 324, may receive a TLSsession response (e.g., a server hello) that includes a securitycertificate. Correspondingly, client 308 may extract the public key fromthe security certificate, may form a hash code using that key, and maycompare the hash code to the hash code embedded in the client codemodule (or hardware component). That is, client 308 may use certificatepinning to authenticate the security certificate received from scanner310 in establishing TLS-1.

However, in establishing the TLS-1 session with client 308, scanner 310may provide (in the response sent at 324) a security certificateassociated with the scanner itself, acting as a proxy for serversaccessed by client 308. Accordingly, the security certificate used tocomplete the TLS-1 session setup includes the public key associated withscanner 310. If client 308 forms a hash code from the scanner 310 publickey, that hash code may not then match the hash code embedded in theclient 308 code module. In response, client 308 may determine thatscanner 310 is not an authentic, trusted server and may abandoncommunications with scanner 310. Consequently, using scanner 310 tointercept and inspect or modify communications with server 306, such asto crawl the backend of client 308, may not be possible in conventionalsystems.

To utilize a scanner (or, proxy) to crawl the backend of a clientapplication, such as disclosed in the foregoing disclosures of FIG. 2and FIG. 3, an analyzer may intercept operations of the client toextract authentication components from within a security certificate,such as a scanner security certificate provided to the client. Theanalyzer then may substitute authentication components from a securitycertificate associated with a server targeted by a client (e.g., toaccess a resource or service hosted by the server) in place ofauthentication components that otherwise might be extracted from ascanner certificate. The client (e.g., client 308), in receiving theauthentication component extracted from the server security certificate,in substitution for the authentication component that may be otherwiseextracted from the proxy security certificate, may then authenticate theproxy (e.g., scanner 310) as trusted.

FIG. 4 illustrates an example communications flow 400 between a clientapplication, a scanner, and a server such that the scanner is able tocrawl client accesses to servers. Client 402 may access server 406 toperform a function. Client 402 may be an application executing on, orwithin, a computing device (e.g., a computer of a form such aspreviously disclosed herein). Client 402 (or, client computer 402) andservers, such as server 406, may be connected to a common network (e.g.,an intranet or the Internet). In other embodiments client 402 (or, theclient computer 402) may be connected directly (not shown) to one ormore servers, such as server 406, or may be, in some other manner, incommunication with client 402 (or, a computing device on, or within,which client 402 executes).

Client 402 may perform particular functions that request a service or aresource (e.g., a WWW page) from server 406. Scanner 404 acts as a proxyfor client 402 accesses to one or more servers, such as server 406.Analyzer 408 interacts 460 with client 402 to activate client functionsthat access server 406. Analyzer 408 may access interfaces (e.g., GUIs,CLIs, or APIs, not shown) of client 402 to activate one or morefunctions that request to access server 406, or resources hosted byserver 406.

In embodiments, analyzer 408 may be may be a program, may be a hardwarecomponent, or may be a combination thereof. Analyzer 408 may be includedin a particular computer (e.g., a server) in communication with, orconnected to a network that connects, client 402. In some embodiments,analyzer 408 may be included in client 402 computer. In embodimentsscanner 404 may be a program, may be a hardware component, or may be acombination thereof. Scanner 404 may be a component of a computer (e.g.,a server) in communication with, or connected to a network thatconnects, client 402 and server 406. In some embodiments, scanner 404may be included in the client 402 computer.

Scanner 404 may crawl the client accesses to a server, or resources of aserver, such as server 406. Analyzer 408 may interact 462 with scanner404 to substitute a security certificate, received by scanner 404 fromserver 406, for a proxy (scanner 404) security certificate, provided byscanner 404 to client 402. In response to the substitution, client 402,performing certificate pinning, may then authenticate scanner 404 toestablish a secure (e.g., TLS) session with scanner 404 and forcommunications between client 402 and server 406.

Scanner 404 may be included in the communications channel (or, path)between client 402 and server 406. Scanner 404 may intercept requests toaccess server 406, and may intercept responses from server 406 directedto client 402, and may forward the requests and responses to theirintended recipient (e.g., client 402 or server 406). Scanner 404 maymodify an intercepted request or response, or may generate, and mayforward, a simulated response from server 406 to client 402.

For purposes of illustrating the disclosure, but not limiting theembodiments, client 402 initiates performing TLS setup 430 to establisha secure TLS session with scanner 404 acting as a proxy. Client 402 mayinitiate TLS setup 430, for example, to access server 406, or resourceshosted by server 406. To initiate the TLS setup, client 402 may send(410) a client hello to scanner 404. Scanner 404, in response, sends(412) a proxy client hello to initiate a TLS session with server 406. Inresponse, server 406 sends (414) a server hello to scanner 404. Theproxy client hello may include a request to server 406 to provide asecurity certificate associated with server 406. Correspondingly, theserver hello may include the requested security certificate and scanner404 may retain a copy of the certificate.

Scanner 404 responds (416) to client 402 with a proxy server hello. Forpurposes of illustrating the disclosure, client 402 and scanner 404exchange cryptographic information and a proxy security certificate bymeans of a client and proxy (server) hello. Accordingly, client 402includes in the client hello, sent at 410, cryptographic information toencrypt subsequent communications, and a request to provide a securitycertificate associated with scanner 404 (acting as a proxy). The scannerat 416 sends a proxy server hello, which includes cryptographicinformation and a proxy security certificate associated with scanner404. In embodiments, a client and proxy may exchange cryptographicinformation, and/or a request for a security certificate andcorresponding response including a security certificate, by means, orprotocols other than a client and proxy hello. In some embodiments, aclient and server may communicate without using encryption, and a clientand server hello may omit cryptographic information to encryptcommunications between them.

In performing TLS setup 430, client 402 performs certificate pinning440. Correspondingly, client 402, at 418, may pass the securitycertificate received at 416 (from scanner 404) to an extraction function(not shown), to extract an authentication component to performcertificate pinning 440. An extraction component may be a program or maybe a hardware component, and may be of the client application or theclient computer. Alternatively, an extraction component may be acomponent of a computer, or computing device, in communication with theclient 402 computer. An extraction component may be a service, and theclient computer, or a component of a computing system (e.g., a server)in communication with the client or client computer, may provide theservice.

Analyzer 408 may instrument, or “hook”, various functions (e.g.,function call APIs, hardware interfaces, or services) provided by theextraction component, such that when client 402 invokes a “hooked”function, the hook pauses, or suspends execution of the client andinvokes a certificate substitution function (not shown). For example, anextraction component may provide a programming function call that client402 invokes to extract an authentication component from a securitycertificate. Analyzer 408 may set, for example, a software trap, orexception call, on various function calls of the extraction component.The trap, or exception, may pause or suspend the client 402 executionwhen client 402 makes that particular function call, and may deliverexecution to, or otherwise invoke, a certificate substitution function.

The certificate substitution function operates to substitute anauthentication component from the server 406 security certificate (sentat 414 to scanner 404) for an authentication component being extractedby client 402 from a security certificate (e.g., the proxy securitycertificate). For purposes of the disclosure, but not limiting theembodiments, analyzer 408 may embody a certificate substitutionfunction, or may interact with a certificate substitution functionembodied in another component of the client computer, or a computer incommunication with the client computer.

In performing certificate pinning 440, client 402, at 418, invokes thehooked extraction function to extract an authentication component fromthe proxy security certificate (received at 416). For example, client402 may invoked the hooked function to extract the public key of theserver from the proxy security certificate. Invoking the hooked functionthen pauses, at 418, the client execution and invokes analyzer 408.While the example method 400 includes hooking an extraction function toinvoke certificate substitution, it would be evident to one of ordinaryskill in the art that an embodiment can utilize other methods to detecta client application extracting an authentication component from asecurity certificate, and to pause execution of the client applicationto perform the features of the method.

In response to the hooked extraction function invoking the certificatesubstitution function, analyzer 408 sends (420) a request to scanner 404to obtain the security certificate received at 414 from server 406.Scanner 404 then returns (422) the server 406 certificate to theanalyzer. Analyzer 408 passes (not shown) to the extraction function(e.g., at 422 or 424), the server 406 security certificate, insubstitution for the proxy security certificate that scanner 404provided at 416 to client 402. The extraction function subsequentlyextracts the authentication component (e.g., the public key of theserver) from the server 406 security certificate (received by scanner404 at 414), in substitution for the proxy certificate sent to client402 at 416.

Analyzer 408, at 424, resumes execution of client 402, passing theextracted server 406 authentication component to client 402. Client 402,at 424, completes certificate pinning 440 using the extracted server 406authentication component. In performing certificate pinning 440 client402 has, or knows, a trusted pin associated with the authentic server406 security certificate. Client 402 forms a pin using the server 406authentication component to compare with the trusted pin and,accordingly, authenticates scanner 404 as trusted and completes TLSsetup 430.

The example TLS setup 430 may permit scanner 404 to subsequentlyreceive, and decrypt, communications (e.g., messages) intended forserver 406, and to receive, and encrypt, communications from server 406(e.g., in response to communications scanner 404 may forward to server406) intended for client 402. In this way, a scanner (or, proxy), suchas scanner 404, may monitor the servers, or resources hosted by servers,accessed by a client application, such as client 402.

FIG. 4 illustrates client 402 performing TLS setup 430 and clientpinning 440 with a single client, client 402, and a single server,server 406. However, it would be apparent to one of ordinary skill inthe art that an embodiment may perform secure session setup (e.g., TLSsetup 430) and client pinning (e.g., client pinning 440) with aplurality of clients and/or servers. Embodiments may perform securesession setup among one client and a plurality of servers, may performsecure session setup among a plurality of clients and a single server,or may perform secure session setup among the plurality of both clientsand servers. Some embodiments may perform secure session setup serially,involving, for example, one particular client and one particular serverat a time. Other embodiments may perform secure session setupconcurrently among the plurality of clients and/or servers. Accordingly,in an embodiment an analyzer may detect (e.g., as part of certificatepinning 440), at any particular time, any of a variety of clientapplications extracting an authentication component from the samesecurity certificate, or from any of a variety of security certificates,associated with one or more of the various servers involved in securesession setup and/or certificate pinning.

In response to authenticating scanner 404 as a trusted server (forexample, by means of certificate pinning 440 using the server 406security certificate) client 402 may access resources and serviceshosted on, or by, server 406. Scanner 404 may receive requests fromclient 402 directed at server 406, and receive responses from server 406directed to client 402. This permits scanner 406 to crawl the backend(450) of the client 402.

Crawling the backend (450) of client 402 may comprise client 402sending, or otherwise communicating, at 426, a server request directedat, or to, server 406 or a resource or service hosted by server 406. Therequest may include a request access to a resource or service providedon or by server 406. Scanner 404 receives (426) the server request andmay inspect the contents of the request, such as to which server (and/orwhich resource or service on the server) client 402 has directed therequest. The scanner may, at 428, forward the client request to server406. Alternatively, scanner 404 may discard the request and, at 432, maysend a simulated server response. A simulated server response mayindicate that the requested server, resource, or service wasunavailable, or not found.

Subsequent to 428, server 406 processes the request and, at 430, mayreturn a response. Scanner 404 (at 430) may inspect the contents of theserver response. The response may include a resource, such as a webpage, or set of web pages, or may include the results of processing aservice request. The response may include a request that client 402provide (not shown) additional information to the server. For example,the response may include a request that client 402 send a user ID andpassword to server 406 to access a resource or service. The response mayinclude data from the server, and the data may be, or be subject, tomalware or another security vulnerability.

Scanner 404, at 432, may forward the server response to client 402.Alternatively, if the scanner determines that the server response at 428presents a security threat, the scanner may determine not to forward(not shown) the server response to the client. Alternatively, scanner404 (at 430) may inspect and/or discard the server response and, at 432,may send a simulated server response. A simulated server response mayindicate that the requested server, resource, or service wasunavailable, or not found.

In some embodiments, a scanner (or, proxy) may crawl a clientapplication backend and may “masquerade” as a server. The scanner (or,proxy) may intercept a server request from a client, may inspect therequest, and may send a response to the client. For example scanner 404,crawling the backend (450) of client 402, may receive the server requestat 426. Scanner 404 may omit, at 428, forwarding the request to server406, and, correspondingly, may omit, at 432, forwarding to client 402 aserver response received at 430. Instead, scanner 404 may inspect therequest received at 426, for example, to determine the web page addressclient 402 targeted. Scanner 404 subsequently, and possibly separatelyor independently of crawling the backend (450) of client 402, may accessthe requested web page and inspect it (and, possibly, other web pages orhyperlinks associated with that web page).

Scanner 404 may generate a response, masquerading as server 406; forexample, scanner 404 may generate and send a response, at 432,indicating (for example) “page not found”. Alternatively, scanner 404may, in response to receiving a server request, at 426, forward theserver request and receive a server response, 428 and 430, and may, at432, omit forwarding the server response and, instead, generate and senda different response (e.g., “page not found”) to client 402.

In an embodiment, a scanner (or, proxy) may not have or make aconnection to a server, or may omit communicating with a server.Accordingly, a scanner (or, proxy) may determine (or, know) a serversecurity certificate by some means other than communications with aserver. For example, scanner 404 may not have or, may omit making, aconnection to server 406. Scanner 404 may omit exchanging the proxyclient hello (412) and server hello (414) with server 406. Accordingly,scanner 404 may know or obtain a security certificate for server 404 bysome other means. For example, scanner 404 may perform the helloexchange, 412 and 414, at some other time, separate or independent ofTLS setup 430, and retain the server 406 security certificate.Alternatively, scanner 404 may perform a proxy client and server helloexchange, and may receive a security certificate from server 404, asillustrated in TLS setup 430. It would be apparent to one of ordinaryskill in the art that there are a variety of methods by which a scanner(or, proxy) may obtain, or be supplied with, a security certificate fora server and, accordingly, omit exchanging a proxy client or serverhello, or equivalents thereof, to obtain a server security certificate.

FIG. 4 illustrates crawling the backend involving a single serverrequest (426) and server response (430). However, it would be apparentto one of ordinary skill in the art that an embodiment may repeat 426,428, 430, and 432 an arbitrary number of times in crawling the backendof the same or various other functions of a client application, such asclient 402. It may be, for example, an objective of an analyzer, such as408, to induce or cause the client to attempt to access various or, allpossible, servers, resources, or services the client may be capable,designed, or intended to access. It may be another objective of ananalyzer to induce or cause the client to attempt to access servers,resources, or services beyond those for which the client is designed orintended.

FIG. 4 illustrates scanner 404 crawling the backend (450) of only oneclient, client 402. However, it would be apparent to one of ordinaryskill in the art that an embodiment may crawl the backend of a pluralityof clients. Some embodiments may crawl the backend of clients serially,involving, for example, one particular client at a time. Otherembodiments may crawl the backend of a plurality of clientsconcurrently. It would be apparent to one of ordinary skill in the artthat an embodiment may crawl the backend of a plurality of clients inany particular order or degree of concurrency, and is not limited by theexamples of FIG. 4.

FIG. 4 illustrates various aspects of the disclosure authenticating aserver in the context of testing a client application and crawling aclient application backend. However, the disclosure of FIG. 4 does notintend to limit the features of the disclosure to testing a clientapplication, crawling a client application backend, or other, particularuses or purposes of a proxy (such as scanning). Rather, the scope of thedisclosure encompasses, and it would be within the skill of one ofordinary skill in the art to apply the disclosure to, any of a varietyof embodiments that include a client authenticating a proxy to receivecommunications between the client and an authenticated server.

FIG. 5 illustrates an example method 500 for authenticating a server, inwhich a client application uses certificate pinning and a proxy is inthe communication path between the client and the server. For purposesof illustrating the method, but not limiting the embodiments, thedisclosure describes the method as performed by an application testplatform. In an embodiment the test platform may be a program, may be ahardware element, or may be a combination thereof, and may execute (oroperate) in or on a client computer of an application-under-test(hereinafter, “client”). In some embodiments, the test platform, orcomponents thereof, may execute in or on one or more computers, orcomputing devices, in communication with a client computer.

The disclosure describes the test platform as including an analyzercomponent and a scanner component. The analyzer may interact with theclient, or the client computer, to cause the client to access one ormore servers or resources hosted by servers in communication with theclient computer (e.g., connected by an intranet or the Internet, or,directly connected, to the client or the client computer). The scannercomponent may be inserted in a communications channel between theclient, or the client computer, and the server(s). The scanner may actas a proxy server to forward client accesses to the servers.

The analyzer and the scanner components may be included in a programexecuting on the same computer, or computing device or system, or may beincluded in programs executing on different computers, computingdevices, or computing systems. In some embodiments the test platform, orthe analyzer or scanner, or other functions or components of the testplatform, may be, wholly or in part, hardware components of a computer,computing device, or computing system. However, it would be apparent toone of ordinary skill in the art that an embodiment may include othercomponents, or functions, in addition to, or in place, of an analyzerand/or a scanner.

Also, for purposes of illustrating the method, the client is describedas establishing a TLS secure session with the scanner, and the scannerestablishing TLS secure session with the server. However, it would beapparent to one of ordinary skill in the art that an embodiment mayperform other methods of establishing a secure session between clients,proxies, and servers. It would be further apparent to one of ordinaryskill in the art that the example method 500, or aspects or featuresthereof, may be applied to any of a variety of embodiments in which aclient application uses certificate pinning to authenticate a server.

The disclosure describes the client computer as having, or being incommunication with a computer or server having, a certificate extractionfunction operating to extract authentication component information froma security certificate. For example, a client may invoke a certificateextraction function to extract a public key from a security certificate.The client may invoke the extraction function by means of a certificateAPI, and the API may be amenable to the test platform detecting theclient invoking the extraction function. For example, the test platformmay be able to instrument, or hook, (e.g., set a software trap orexception within) an extraction function of the API.

However, it would be apparent to one of ordinary skill in the art that aclient application may use a variety of components, or functions, of acomputing device or computing system to extract authenticationcomponents from a security certificate. It would be further apparent toone of ordinary skill in the art that a test platform may havecorresponding other means to detect the client invoking another type ofcomponent, or function, to extract authentication components from asecurity certificate, and to perform features of the method.

Referring to FIG. 5, at 504, the test platform hooks one or moreextraction functions of the certificate API. At 506, the analyzeractivates a function of the client. The analyzer may access an interfaceto a function of the client, such as an interface (e.g., an input field,a command, or a function call) included in a client GUI, CLI, or otherAP, to activate the function. Activating the client function, at 506,may cause the client to access a server, or a resource hosted by aserver (e.g., a web page or service). Further, the client accessing theserver or resource may cause the client to initiate establishing a TLSsecure session with the scanner (operating as a proxy).

Accordingly, at 508 the scanner receives a communication from theclient—for example, a client hello—to initiate the TLS secure session.The client hello may include the identity (e.g., an IP address or a WWWURL) of the server, or of a resource or service hosted on, or by, theserver. The client hello includes a request to provide a securitycertificate associated with the server. Correspondingly, at 510 thescanner initiates establishing a TLS secure session with the servertargeted by the client hello. At 510, the scanner sends a proxy hello tothe target server and includes, in the proxy hello, information toinitiate establishing the TLS session with the server. The proxy helloincludes a request for the server to provide the scanner with a securitycertificate associated with the server. Correspondingly, at 512, thescanner receives, from the server, a server hello and the server helloincludes the server security certificate requested by the scanner at 510and, at 514, the scanner stores the server certificate.

To complete establishing the TLS session with the client, at 516 thescanner responds to the client hello (from 508) with proxy server hello,which includes cryptographic information and a security certificateassociated with the scanner (as a proxy). The client utilizescertificate pinning to authenticate the scanner as a trusted server. Theclient passes the proxy server certificate, received at 516, to theextraction function, to extract an authentication component, such as thepublic key of the server, from the proxy security certificate and toform a pin to compare with a trusted pin associated with the server.

In some embodiments, a proxy may not have, or may omit making, aconnection to a server, or may not exchange a proxy and server hello,and, correspondingly, may omit 510 and 512. Accordingly, a proxy (e.g.,the scanner) may know, or may obtain, a server security certificate byanother means. For example, a proxy may make a connection to a serverand may perform 510 and 512 separately from, or independently of, method500. In an embodiment, another component of a test platform (e.g., ahuman user, or a program, testing an application), or a computingsystem, may supply a proxy with a server security certificate. It wouldbe apparent to one of ordinary skill in the art that there are a varietyof methods by which a proxy may obtain, or be supplied with, a securitycertificate for a server and, accordingly, omit 510 and 512.

At 518, the client accessing the hooked extraction function invokes theanalyzer (as embodying the certificate substitution function).Accordingly, at 520 the analyzer (or, for example, the hook that invokedthe analyzer, such as a trap or exception) pauses execution (or,operation) of the client. At 522, the analyzer communicates with thescanner to retrieve the server security certificate and, at 524, theanalyzer passes the server security certificate to the extractionfunction, in substitution for the proxy security certificate passed, at518, from the client to the extraction function.

The analyzer (or, a proxy) retrieving the server security certificate,at 522, may involve various communications between the analyzer and thescanner. For example, the analyzer may send a message to the scannerrequesting the server certificate. The analyzer may send the messageutilizing a communications channel established between the client (e.g.,a TCP session such as disclosed in reference to FIG. 1), or utilizinganother, alternative communications channel. The analyzer may send themessage utilizing a secure communications session established betweenthe client and scanner at 508 through 516. The scanner may respond andreturn the server security certificate using the communications methodused by the analyzer to request the certificate.

In other embodiments, the analyzer and scanner may be components of aprogram, or included in components of the client computing device, andthe analyzer may have an API to invoke a function (e.g., a programmingfunction call) of the scanner, from which the scanner may return theserver security certificate as a return argument or parameter. In yetother embodiments, the analyzer may have direct access (e.g., to storageused by the scanner) to the server security certificate. It would beapparent to one of ordinary skill in the art that there are a variety ofmethods by which an analyzer, or another function of a computer orcomputing system, may retrieve a server security certificate in order topass the certificate, at 524, to the extraction function.

At 524, the analyzer passes the server certificate, received at 522, tothe extraction function, and at 526, resumes the client execution. Uponresuming execution (or, operation), the extraction function returns theresults of the function invoked at 518 to the client. Resuming executionof the client may be a function of the analyzer, or may be a function ofthe manner in which the client invoking the API function was, at 516,detected and the analyzer invoked. For example, the detection may havebeen by means of a software trap or exception, and the program thathandles the trap or exception may resume execution of the client at 526.It would be apparent to one of ordinary skill in the art that a varietyof functions of a test platform, or a computing system (or, an operatingsystem executing a client application or function of a test platform,for example) may resume execution of the client. Resuming execution (or,operation) of the client may be in accordance with the means by which,at 518, the test platform, or computing system, paused client execution.

At 528, in resuming operations, the client forms a pin using theauthentication component extracted at 524 from the server securitycertificate, compares the pin to a trusted pin associated with theserver, authenticates the scanner (or, a proxy) as trusted, andcompletes establishing the TLS session. Having established the TLSsecure session between the client and the scanner, the analyzerinteracts (at 528) with the client to activate client functions thataccess the server, or resources or services hosted on or by the server.As the client requests access and the server responds to the requests,the scanner crawls (at 528) the backend of the client.

As disclosed in reference to FIG. 4 regarding crawling the backend (450)of a client application, it would be apparent to one of ordinary skillin the art that method 500 may involve a plurality of clients and/orservers. It would further be apparent to one of ordinary skill in theart that an embodiment may perform method 500, or elements thereof, inany particular order or degree of concurrency, with respect to theplurality of the clients and/or the servers, and interaction of ananalyzer with a plurality of clients.

The structures and methods of the disclosure are amenable to embodimentin an article of manufacture or computer program product. FIG. 6 depictsan article of manufacture or computer program product 600 that is oneexample embodiment of the invention. The computer program product 600may include a recording medium 602, and the recording medium 602 maystore program modules 604, 606, 608, and 610 for a computer to carry outthe aspects of the invention. The recording medium 602 may be a CD ROM,DVD, tape, diskette, non-volatile or flash memory, storage mediumaccessed by a network connection, or other similar computer readablemedium for containing a program product.

A sequence of program instructions within, or an assembly of one or moreinterrelated modules defined by, the program modules 604, 606, 608, and610 may direct a computer to implement the aspects of the inventionincluding, but not limited to, the structures and operations illustratedin and described in the present disclosure.

The present invention may be a system, a method, and/or a computerprogram product at any possible technical detail level of integration.The computer program product may include a computer readable storagemedium (or media) having computer readable program instructions thereonfor causing a processor to carry out aspects of the present invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, configuration data for integrated circuitry, oreither source code or object code written in any combination of one ormore programming languages, including an object oriented programminglanguage such as Smalltalk, C++, or the like, and procedural programminglanguages, such as the “C” programming language or similar programminglanguages. The computer readable program instructions may executeentirely on the user's computer, partly on the user's computer, as astand-alone software package, partly on the user's computer and partlyon a remote computer or entirely on the remote computer or server. Inthe latter scenario, the remote computer may connect to the user'scomputer through any type of network, including a local area network(LAN) or a wide area network (WAN), or the connection may be made to anexternal computer (for example, through the Internet using an InternetService Provider). In some embodiments, electronic circuitry including,for example, programmable logic circuitry, field-programmable gatearrays (FPGA), or programmable logic arrays (PLA) may execute thecomputer readable program instructions by utilizing state information ofthe computer readable program instructions to personalize the electroniccircuitry, in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause the computer, other programmable apparatus, or other device toperform a series of operational steps to produce a computer implementedprocess, such that the instructions which execute on the computer, otherprogrammable apparatus, or other device implement the functions/actsspecified in the flowchart and/or block diagram block or blocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the blocks may occur out of theorder noted in the Figures. For example, two blocks shown in successionmay be executed substantially concurrently, or the blocks may sometimesbe executed in the reverse order, depending upon the functionalityinvolved. It will also be noted that each block of the block diagramsand/or flowchart illustration, and combinations of blocks in the blockdiagrams and/or flowchart illustration, can be implemented by specialpurpose hardware-based systems that perform the specified functions oracts or carry out combinations of special purpose hardware and computerinstructions.

The descriptions of the various embodiments of the present disclosurehave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

What is claimed is:
 1. A method for authenticating a server, the methodcomprising: receiving, from a client, a client request for a securitycertificate, the client communicatively coupled to a hosting server;communicating to the client, in response to the request for the securitycertificate, a proxy security certificate, the proxy securitycertificate associated with a proxy, the proxy security certificateincluding a first server authentication component, the proxy interposedin the communication path between the client and the hosting server;detecting, by a computer, the client extracting the first serverauthentication component from the proxy security certificate; pausingoperation of the client in response to the detecting the clientextracting the first server authentication component; extracting asecond server authentication component from a hosting server securitycertificate, the hosting security certificate associated with thehosting server; and resuming operation of the client, wherein resumingoperation of the client includes the client completing the extractingthe first server authentication component from the proxy securitycertificate using the extracted second server authentication componentin substitution for the first server authentication component, theextracted second server authentication component, in substitution forthe first server authentication component, operating to authenticate theproxy to receive client communications directed to the hosting server.2. The method of claim 1, wherein the detecting the client extractingthe first server authentication component from the proxy securitycertificate comprises instrumenting an extraction function, theextraction function operative to extract the first server authenticationcomponent from the proxy server security certificate, the instrumentingoperative to detect the client accessing the extraction function.
 3. Themethod of claim 1, further comprising the proxy receiving a clientcommunication, the client communication directed to the hosting server,wherein the proxy receiving the client communication is based, at leastin part, on the extracted second server authentication componentauthenticating the proxy to receive client communications directed tothe hosting server.
 4. The method of claim 3, wherein the proxyreceiving the client communication is in response, at least in part, toactivating a function of the client, the function producing the clientcommunication directed to the hosting server.
 5. The method of claim 3,further comprising scanning the client communication for the identity ofat least one of a resource or a service, the at least one of theresource or the service hosted on at least one of the hosting server ora computing system in communication with the hosting server.
 6. Themethod of claim 1, further comprising the proxy obtaining the hostingserver security certificate from the hosting server.
 7. The method ofclaim 1, wherein the client extracting the first server authenticationcomponent from the proxy security certificate is based, at least inpart, on the client performing certificate pinning authentication of thehosting server; and wherein using the extracted second serverauthentication component, in substitution for the first serverauthentication component, satisfies the certificate pinningauthentication.
 8. A computer program product comprising a computerreadable storage medium having program instructions embodied therewith,the program instructions executable by a first computing device toperform a method comprising: receiving, from a client, a client requestfor a security certificate, the client communicatively coupled to ahosting server; communicating to the client, in response to the clientrequest for the security certificate, a proxy security certificate, theproxy security certificate associated with a proxy, the proxy securitycertificate including a first server authentication component, the proxyinterposed in the communication path between the client and the hostingserver; detecting the client extracting the first server authenticationcomponent from the proxy security certificate; pausing operation of theclient in response to the detecting the client extracting the firstserver authentication component; extracting a second serverauthentication component from a hosting server security certificate, thehosting server security certificate associated with the hosting server;and resuming operation of the client, wherein the resuming operation ofthe client includes completing the client extracting the first serverauthentication component; wherein the completing the client extractingthe first server authentication component provides the client with theextracted second server authentication component in substitution for thefirst server authentication component; and wherein the extracted secondserver authentication component, in substitution for the first serverauthentication component, operates to authenticate the proxy to receiveclient communications directed to the hosting server.
 9. The computerprogram product of claim 8, wherein the detecting the client extractingthe first server authentication component from the proxy securitycertificate comprises instrumenting an extraction function, theextraction function operative to extract the first server authenticationcomponent from the proxy security certificate, the instrumentingoperative to detect the client accessing the extraction function. 10.The computer program product of claim 8, wherein the programinstructions are further executable by the first computing device tocommunicate to the proxy a client communication directed to the hostingserver, and communicating the client communication to the proxy is basedat least in part on the client using the second server authenticationcomponent to authenticate the proxy to receive client communicationsdirected to the hosting server.
 11. The computer program product ofclaim 10, wherein the program instructions are further executable by thefirst computing device to communicate to the proxy the clientcommunication directed to the hosting server, at least in part, inresponse to activating a function of the client, the function producingthe client communication directed to the hosting server.
 12. Thecomputer program product of claim 10, wherein the program instructionsare further executable by the first computing device to scan the clientcommunication for the identity of at least one of a resource or aservice, and wherein the at least one of the resource or the service ishosted on at least one of the hosting server or a computing system incommunication with the hosting server.
 13. The computer program productof claim 8, wherein the program instructions are further executable bythe first computing device to obtain the hosting server securitycertificate from the hosting server.
 14. The computer program product ofclaim 8, wherein extracting the first server authentication componentfrom the proxy security certificate is based, at least in part, on theclient performing certificate pinning authentication of the hostingserver; and wherein using the extracted second server authenticationcomponent, in substitution for the first server authenticationcomponent, satisfies the certificate pinning authentication.
 15. Asystem for authenticating a server, the system comprising: a firstcomputing device, the first computing device including a firstprocessor; a client, the client included in the first computing device;a hosting server, the hosting server including a second processor, thehosting server communicatively coupled to the client; a proxy, the proxyincluded in a second computing device, the second computing deviceincluding a third processor, the proxy interposed in the communicationpath between the client and the hosting server; and an analyzer includedin a third computing device, the analyzer communicatively coupled to theclient, the third computing device including a fourth processor; whereinthe proxy is configured to receive a client request for a securitycertificate; wherein the proxy is configured to communicate to theclient, in response to the client request for the security certificate,a proxy security certificate, the proxy security certificate associatedwith the proxy, the proxy security certificate including a first serverauthentication component; wherein the client is configured to extractthe first server authentication component from the proxy securitycertificate; wherein the analyzer is configured to detect the clientextracting the first server authentication component from the proxysecurity certificate; wherein the analyzer is configured to pauseoperation of the client in response to detecting the client extractingthe first server authentication component; wherein the analyzer isconfigured to extract a second server authentication component from ahosting server security certificate, the hosting server securitycertificate associated with the hosting server; wherein the analyzer isconfigured to resume operation of the client, the resuming the operationof the client including the analyzer providing to the client theextracted second server authentication component in substitution for thefirst server authentication component; and wherein the client isconfigured to authenticate the proxy to receive client communicationsdirected to the hosting server based, at least in part, on the clientreceiving the extracted second server authentication component insubstitution for the first server authentication component.
 16. Thesystem of claim 15, wherein the analyzer is configured to detect theclient extracting the first server authentication component from theproxy server security certificate using instrumentation of an extractionfunction, the extraction function operative to extract the first serverauthentication component from the proxy server security certificate. 17.The system of claim 15, wherein the client is configured to communicateto the proxy, based at least in part on the client authenticating theproxy to receive client communications directed to the hosting serverusing the extracted second server authentication component provided tothe client by the analyzer, a client communication directed to thehosting server.
 18. The system of claim 17, wherein the client isconfigured to communicate the client communication to the proxy at leastin part in response to the analyzer activating a function of the client,the function producing the client communication directed to the hostingserver.
 19. The system of claim 17, wherein the proxy is configured toscan the client communication for the identity of at least one of aresource or a service, the at least one of the resource or the servicehosted on at least one of the hosting server or a computing system incommunication with the hosting server.
 20. The system of claim 15,wherein the client is configured to perform certificate pinningauthentication of the hosting server; and wherein the client using theextracted second server authentication component, provided to the clientby the analyzer, satisfies the certificate pinning authentication toauthenticate the proxy to receive the communications directed to thehosting server.